This invention relates to the production of pile fabric on a loom having a pile-warp beam, a ground-warp beam, and a batten the stroke of which during operation is periodically decreased from the value corresponding to a full stroke of the batten by a value for partial strokes which is referred to as the pre-beating distance.
In the manufacture of pile fabric, it is necessary, in order to obtain goods of good quality, that the quantity of pile-warp yarns fed and the pile-warp tension in the shed be as constant as possible. This requirement is imposed by the fact that variations in the ground-warp tension affect the pre-beating distance, which results in irregularities in the height of the pile.
The influence of changes in the ground-warp tension on the height of the pile results from the fact that with an increase in the tension of the ground warp, the so-called cloth advance, that is the movement of the fell of the cloth upon the backward swinging of the batten from its defined position in the direction towards the batten, becomes smaller so that the following pre-beating distance becomes greater. This in its turn leads to a greater height of pile.
The closest prior art known to the inventor is U.S. Pat. No. 4,112,981.